Sound-modifying reproducer for phonographs.



G. G. CARLSON. SOUND MODIFYING REPRODUCER FOR PHONOGRAPHS APPLIGATLON TILED AIRJL H12 1 ,077,593, Patented N0v.4,1913.

XII/M section of the sound box.

UNITED STATES PATENT OFFICE.

CARL G. CARLSON, F HAWTHORNE, ILLINOIS.

SOUND-MODIFYING REPRODUCEB FOR PHONOGRAPHS.

Application filed April 3, 1912. Serial No. 688,146.

To all whom it may concern ful Improvements in Sound-Moditving licproducers for Phonographs, of which the following is a specification.

My invention relates to phonographs, and I particularly to the sound boxes or reprw made to more or less register with the open-- (lucers thereof, and the primary object of my invention is to provide means whereby ably provided with a slot 14 through'which the degree of loudness of the sound may be modified to any desired degree so that the reproduction will either be relatively faint or relatively loud as may be desired.

Other objects will appear in the course of the following description. My invention is illustrated panying drawings wherein:

Figure 1 is a perspective view of a poriu the accomtion'of a phonograph horn with my sound box applied thereto. Fig. 2 is a diamctrical Fig. 3 is a face view of the sound box, the diaphragm being removed and the wall of the sound box being in section.

Referring to these drawin s, 2 designates a sound box such as is used in connection with disk record machines. circular in form as usual, and is provided with the usual annular wall 3 upon which the diaphragm 4, which as shown is made of mica or like substance, is supported in any usual or suitable manner. Attached to the wall 3 is the bracket 5 supporting the stylus arm 6 which as usual is turned inward at one end and engaged with the ce n-.

ter of the diaphragm. The extremity of the bracket 5 is formed with a socket for the reception of the stylus or needle 7 which is held in place by means of a set screw 8. I wish it understood that any suitable means for holding the stylus arm 6 or the needle may be rovided as this construction may be modi ed in many ways without departing from the spirit of the invention.

The sound box 2, which is preferably made of metal,is provided with a sounddischarging opening designate 9 which is located, not at ,he axial center of the sound box but eccenf cally thereto, and extending from this open ng 9 is the tube 10 adapted to be connected if desired to a horn in the usual manner, or the sound box maybe used Specification of Letters Patent.

This sound box Paten ted 0v. 4, 1 913.

. without the born as is usual in cabinet ma- Be 1t known that I, CARL G. (launsox, citizen of the United States, residing at Hawthorne, in the county of Cook and State of Illinois, have invented certain new and usechines. v

Mounted within the sound box and restin against the inner face thereof is a cut-o I plate designated 11 of less diameter than the i box and pivoted at. 12 so that it may be'ro tated in the arc of a circle. This plate .11 is termed with an opening designated'13 having the same size as the opening 9, and aspasses a pin 15. On the pin is a head 16. The head 16 has screw threaded engagement with the pin 15. so that when the head is turned home it will bite against the outer face of the bottom of the sound box and .will be seen that if it is desired that only a. relatively faint sound shall issue from the sound box, the plate 11 is so turned that only a very small portion of the. openin 9 is uncovered, but that if it is desired t at the full sound shall issue from the sound box, then the plate 11 is so turned that the opeuing 13 fully registers with the opening 9. It will be obvious that the plate 11 may be so adjusted as to vary the sound discharge opening from the maximum to the minimum, or that it may be so shifted as to cut off the opening 9 entirely. Thus the sound issuing from the sound box may be of full strength or weakened t9 any desired degree. It is further pointed out that by reason of the fact that the opening 9 is set eccentrically to the center of the box, the box may be turned relatively to the support upon which the sound box is mounted so as to cause the needle 7 to bear with more or less force upon the face of the record, and

It is simple 1]! construction box, a pin extending centrally through said in the box, said platenbeing of adiameter and extremely simple in operation. The parts are very-few and any one can operate the device.

What I claimis:

A sound box for sound reproducing machines having a sound discharge opening eceentrically set with relation to the box and arranged to communicate with the sound tube of the machine, a plate disposed withslightly less than the inner diameter of'the plate and the rear wall of the box, the terminal of said pin which projects through the rear wall of the box being threaded to receive jam nuts; the rear Wall being provided with an arcuate slot, :1 pin supported by the plate and disposed to extend through said arcuate slot, said pin remote from tne Plate being threaded, a pm nut mounted on the threaded portion of the pin, said nut con-' tacting with the outer face of the rear wall of the box to lock the plate against movement, the plate being providedwith an eccentrieally disposed sound discharge opening arranged to register with the opening in the rear wall of the box.

In testimony whereof I aifix my signature in presence of two Witnesses. 

